Improved safety-valve arrangement



p V UNITED STATES PATENT OFFICE.

wiLLrAt/r s. HUNTINGTON, on` ANDEUsvILLE, NEW vonk, AssIGNon To HIMSELFAND JAMES RUBERTSON, OF ALEXANDRIA, VIRGINIA.

i IMPROVED sAFETYvALVE ARRANGEMENT.

Specification forming part of Letters Patent No. 411,580, 'datedFebruary 9, 186i;v

To all whom it may concern:

Be it known that I, W1LLIAMS.HUNT1NG TON, of Andrusville, in the countyof Franklin and State of New York, have invented a new and ImprovedSafety-Valve Regulator for Steam-Boilers; and I do hereby declare thefollowing to be a full and exact description of the same, referencebeing had to the accompanying drawings, making part of thisspecification, in whichn Figure l is a side elevation of a steam-boilerand dome with my invention applied. Fig. 2 is a sectional elevation ofthe same, the section being taken in the line x, Fig. 3. Fig.

3is a section in the line y y, Fig. 1, looking from above. Fig. 4 is anend elevation.

Similar letters of reference-indicate corresponding parts in the severalviews. y

The object. of this invention is to produce a valve and devices'forautomatically operating the same to be employed in connection with or inaddition to the ordinary safety-valve, and designed to preclude thepossibility of explosion in cases where steam is being blown oft' at theprimary valve, but where the port of the latter is of too limiteddimensions to permit the escape of steam in sufficient quan tity, orwith the expedition which the excessive pressure or surplus thereofdemands.

In order that others skilled in the art to which my invention appertainsmay be enabled to fully understand'and use the same,

' I will proceed to describe its construction and operation.

In the accompanying drawings, A may represent a boiler, and B asteam-dome mounted thereon, The steam-pipe within the dome may be closedby a valve of any suitable construction, which valve is attached to theend of the lever C in customary manner, the said lever C being at itsopposite end connected to the spring balance or gage D.

E is a rod pivoted at its respective ends to the lower end of thesteam-gage D, and to the upper end of a sliding rack, F, which movesvertically in ways G, secured within a circular guide, H.

I represents a oogged segment formed upon or rigidly affixed to the endof a lever, I', and pivoted at or near its junction with the lever I intheA horizontal bars I2, which latter may be formed with or secured inthe: guide H.

The segment I is `secured in such position that its teeth work withinthe teeth ot the rack F, so that by the turning ot' the lever I theposition of said rack maybe varied in height for the purpose to beexplained.

J represents a screw or pin secured in the lever I at a point slightlyabove the guide H, and forming a support and pivot for a catch or pawl,K, which is adapted to bc retained in either of a series of notches, h,in the guide H, by a spiral spring, It, encircling the screw J.

L represents arod, jointed at its upper end to a lug, c, formed upon anddepending from the lever O, and at its lower end to a bent arm, M,which, when the rod L is elevated by asimilar movement of the valve-rodC, is adapted to partially rotate a cam, N, so as to throw the springcatch or pawl K out of the uppermost notch in the guide H for thepurpose of permitting the valve covering the steam'pipe Within the domeB to be elevated,

as will be explained. The shaft n, upon which the cam N is keyed, hasits bearings in a lug, a', and a suitable box, N.

Operation: It will, ot' course, be understood that the valve upon thelever C is to be held within its seat by power more or less in excess ofthat applied to the prim ary valve-that is to say, that a somewhathigher pressure of steam will be required to elevate the valve upon thelever O from its seat than to open the port of the primary valve. Theparts being in the position shown in Fig. l, it will be supposed thatthe primary valve has been opened by a high pressure of steam. If, whenthe primary valve is in its open condition, the volume of steam withinthe -boiler suddenly increases to such an extent that the dimensions ofsaid primary valve are too limited to admit ofthe escape of steamthrough the same in quantity or rapidity commensurate with such suddenincrease in volume, the steam contained in the pipe within the dome Bacts upon the valve'on the Vlever O, and exerts a pressure thereon untilthe weight at which the gage D may be set is overbalance. The valve isthen at once opened and the steam discharges itself in a volume ot amplesize to preclude the possibility of explosion. The gage is so arrangedthat when the index thereof has reached the point at which the valveshould be allowed to open the bent arm M is by the rod L caused to actupon the cani N, in order to throw the pawl K out of the uppermost notchin the guide H, whereupon the lever I', being released, adapts thecogged segment I to be freely turned upon the pivot in the bars l2, sothat the rack F will be therebv :released and the lever G allowed toascend. l

lt will be apparent that the valve upon the' lever G may be readilyrestored to its closed position by turning the lever I till the pawl K,again takes into the uppermost notch in the guide H. By adjusting thepawl K in either otl the remaining notches h the pressure required toelevate the valve on the lever C may be lessened as circumstances mayrender needful. Having thus described lnyv invention, the

following is what I claim as new therein and

